Hatchback Door Water Ingress

[Chiguy]

Just had need to open the hatchback door. Following yesterday's "autumn deluge" on opening the door above the horizontal, a significant amount of water poured from the inner door trim into the vehicle which could only have accumulated during the periods of rain. Seems a bit strange that (a) water could penetrate into the car interior inthe first place, and (b) that it did not drain out through the three drainage holes in the bottom of the door. Will investigate further, but has anyone else experienced this ?